Over-temperature alarm using operational amplifier.

This over-temperature alarm circuit uses a common semiconductor diode as a temperature sensing element.

This 2 LED Temperature change indicator shows us, by means of two LEDs, when the sensed temperature is above or below a set limit.

When the temperature is above the pre-set temperature level, LED D1 will light up and if it is below, LED D2 will light up.

Soldering Iron Temperature Controller (circuit)

Very simple soldering Iron temperature controller system You can do by yourself. It uses very few components. Ideal for DIY projects and circuits

Temperature alarm circuit with 741 operational amplifier

This temperature alarm circuit with operational amplifier activates a relay when the temperature of the place to be controlled exceeds a set level. Useful for an oven temperature control or a cooling system

Over temperature alarm circuit using Thermostat

This alarm circuit uses the 67L080 thermostat (TH) and can be assembled easily, due to the small number of components required.

Differential Temperature Controller.

This circuit measures the temperature difference between 2 sensors and activates a relay when they are different. It is also possible to detect a temperature change, even when the two measured temperatures are normally different.

This temperature to voltage converter circuit, convert the sensed temperature by a thermistor into a voltage level.

The circuit achieves an acceptable performance between 0 and 24°C

Temperature gauge circuit using the LM324 IC

The temperature level is displayed using 4 LEDs:
A green LED indicates that the temperature is OK.
Two yellow LEDs indicate that the temperature is higher than normal.
A red LED indicates that the temperature is very high